While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Weatherford International (NYSE:WFT) climbed 1.5% today after Global Hunter Securities upgraded the oil-field services specialist from neutral to buy.

So what: Along with the upgrade, analyst Mark Brown boosted his price target to $28 (from $18), representing about 37% worth of upside to Friday's close. So while contrarian traders might be turned off by Weatherford's sharp rise in recent months, Brown's call could reflect a strengthening sense on Wall Street that the company's growth prospects still aren't fully baked into the valuation.

Now what: According to Global Hunter, Weatherford's risk/reward trade-off remains rather attractive at this point. "WFT delivered a typically messy quarter with below-consensus operating results (adjusted EBITDA of $637MM vs. $648MM consensus) but better-than-expected Q2:14 EPS guidance of $0.21-$0.23 (vs. $0.18 consensus) and a roadmap with a few milestones checked off now (and a few more penciled in) toward the completion of its transformation plan," said Brown. "We believe the company is on track to wrap up its cost reduction initiatives (toward $0.30 per share of annualized savings) by Q2:14 and curtail its exposure to four remaining non-core businesses (testing & production services, US drilling fluids, wellheads, and international land rigs) by Q1:15." Of course, when you couple Weatherford's red-hot stock price with its still-hefty debt load, I'd wait for a wider margin of safety before buying into that bullishness.